Electrical connector contact crimping tool



Oct. 23, 1962 MORRls 3,059,511

ELECTRICAL CONNECTOR CONTACT CRIMPING TOOL Filed Aug. 27, 1958 3 Sheets-Sheet 2 0 j N m E I t m a: a

I N E l'\ INVENTOR JAMES E. MORRIS BY wag ATTORNEY Oct. 23, 1 J. E. MORRIS ,5

ELECTRICAL CONNECTOR CONTACT CRIMPING TOOL Filed Aug. 27, 1958 3 Sheets-Sheet 3 INVENTOR. JAMES E. Mom/s.

M3477 QNEV.

rates Fiied Aug. 27, 1958, Set. No. 757,514 8 Claims. (Cl. 81-15) This invention relates to crimping tools and more particularly to crimping tools which automatically apply the required amount of pressure for securing connectors to various size wires and which position the crimp along the axis of the contact as desired.

Heretofore crimping tools have been used for making crimps in a connector barrel to secure it to an electrical conductor. This provides for physical and electrical contact without the necessity of soldering. However, care must be exercised to insure that a crimp of sufiicient depth has been made to prevent accidental disengagement of the connector with the conductor. Also, if excessive pressure is applied, the connector barrel becomes distorted and its walls may become out or broken. Since the connector has a barrel portion to receive the conductor and a pin portion extension which will not receive the conductor, the position of the crimp along the connector axis must be accurate in order to insure crimping action with the conductor. Additional crimping of the connector to the insulation on the conductor for greater strength is sometimes desirable, requiring a second crimping spaced along the connector axis from the first crimp. While a length adjustment attachment for crimping tools is currently available, it requires that a connector well nut be manually adjusted until the centerline of the nut is properly set. This requires continuous adjustment in placing more than one crimp axially along the connector.

The connector contact crimping tool comprising the present invention provides for a ratchet mechanism to prevent withdrawal of the connector from the punch holder until the handles of the tool have been completely closed to insure sufficient crimping action regardless of the size of the wire and connector being crirnped. An overload release mechanism is provided to limit the crimping pressure applied against the connector so that excessive pressure will not break, cut or unduly distort the connector, irrespective of its size. This is done by stopping further inward movement of the punches against the connector with continued inward movement of the handles. A depth selector with a positive stop is provided to accommodate various lengths of connector pins and barrels. For connectors requiring a second axial crimp, a trigger mechanism is provided to readily permit a positive pre determined axial spacing of the second crimp from the first. Once the tool is set for crimping of a certain depth no further adjustment is necessary and connectors and conductors may be crimped together in a speedy mass production manner without adjustment to provide for their size.

It is therefore an object of the present invention to provide for a new and improved crimping tool.

Another object is the provision of a crimping tool which automatically applies a uniform pressure to connectors and conductors irrespective of their various sizes.

Another object is the provision of a crimping tool wherein a predetermined minim-urn crimping pressure must be applied before the tool punches may be withdrawn from contact with the connector being crimped to its associated conductor.

Another object is the provision of a crimping tool wherein excessive pressure will operate an overload release mechanism to prevent crimping too deeply, thereby I atet cutting, breaking or unduly distorting the connector being crimped.

Another object is the provision of a crimpingtool having a plurality of quickly adjustable positive stops foraxially positioning the crimping of a connector atpredetermined distances from its tip.

Another object is the provision of a crimping tool hav ing a stop release to permit the crimping of a connector in axial spaced relation from a first crimp.

Another object is the provision of a crimping tool which automatically applies a pressure within predetermined minimum and maximum limits to all sizes of connectors and conductors within wire sizes #28 through #10 without manual adjustment for crimp indentations.

Other objects and features of the present invention will be readily apparent to those skilled in the art from the following specification and appended drawings wherein is illustrated a preferred form of the invention, and in which:

FiGURE 1 is a side elevational view with portions thereof broken away to better illustrate tool operation,

FIGURE 2 is an elevational view of the top handle before assembly with the bottom handle and with a side plate removed,

FIGURE 3 is an elevational view of the bottom handle with rack attached,

FIGURE 4 is a perspective view of the overload release plate,

FIGURE 5 is a top plan view showing the depth selector mounting, and

FIGURE 6 is an exploded perspective view of the depth selector mechanism.

This invention relates generally to an improved crimp ing tool of the type having two relatively movable handle members 11 and 12 adapted to be pivotally connected at one of their extremities. Handle member 11 is generally U-shaped in section formed by a body portion 13 and a pair of side plates 14, 16 which have enlarged sections 17 at the pivotal extremity. These plates have aligned openings 18 for receiving the connector to be crimped; Slotted openings 19 are arranged symmetrically about and spaced radially from the central opening 18 and'are designed to accommodate fastening units 21 such as bolts, rivets or the like when the component parts of the tool are assembled. Handle member 12 has a structuralcom figuration similar to that of handle member 11 except that it is preferably constructed of solid material, such as cast iron for example, and its enlarged extremity 22 is adapted to fit between plates 14, 16. This enlarged extremity 22 has an enlarged opening 23 whose center is in axial alignment with the center of opening 18' in the plates 14, 16. This opening 23 in handle member 12 has a series of cam surfaces 24 about its periphery.

A cylindrical punch holder 26 is adapted to rotate within the enlarged opening 23. This punch holder 26 also has a central opening 27 in axial alignment with the outer opening 18 to accommodate the connector inserted therein. Extending radially from the central opening 27 of the punch holder 26 and intermediate the side walls thereof are a series of passageways 28, preferably four in number spaced at ninety degree interval-s. These passageways 28 are preferably circular in section and con tain a shoulder 29 defined by the junction between an inner constricted portion 31 and an outer larger portion 32. Disposed in the passageways 28 are forming punches 35, each having an enlarged head portion 34 thatengages cam surface 24 on handle member 12 and a cylindrica-l'body portion 36 integrally connected with the headportion 34 and being provided with a connector engaging tip 37. A spring member 38 located between the bottom surface of head portion 34 and the shoulder 29' urges the forming punch 33 into contact with the cam surface 24. It may be readily appreciated that rotation of the punch holder 26 in a clockwise direction will cause the cam surfaces 24 to 'force the forming punches 33 inwardly against the action of spring member 38. The punch holder 26 is caused to rotate clockwise as handles .11 and 12 are brought together because of its connection with the top handle side plate 14, 16 and overload release plate 39 positioned therebetween on both sides of the punch holder 26. This rotation is directly related to handle movement until an excessive force is applied, after which the overload release mechanism permits further handle movement without further punch holder rotation. Overload release plate 39 consists of a pair of rotatable faces 41 riveted, bolted or otherwise secured to punch holder 26 by fastening means 21 so as to rotate therewith and to prevent relative rotation therebetween. The two faces 41 extend toward the handle ends of the tool and terminate with an integral transverse connector 43 upon which rollers 44 ride. Fastening means 21 extend outwardly from the faces 41 of the clutch plates and engage slots 19 in the top handle side plates 14, 16. Normally the fastening means 21 will engage the clockwise end 43 of the slots 19 and the overload release plate 39 and punch holder 26 will rotate in direct response to movement of handle 11 relative to handle 12. However, forces in excess of the desired crimping force on the punch tips 37 permit continued clockwise rotation of handle 11 without further notation of the punch holder 26 or clutch plates 39. When this happens the fastening means 21 engages the counterclockwise end 47 of the slots 19.

When a connector exerts a force against the punch tips 37, as when a larger size connector is being crimped, the frictional force between punch head 34 and cam surface 24 is too great to permit further relative movement therebetween, and prevents further rotation of the punch holder 26 and overload release plate 39. This fixes the position of the transverse connector 43 upon which roller 44 is adapted to move. The roller 44 is mounted at the pivotal connection 49 between bar 51, which is pivotally mounted to the top handle 11 at a point 52 slightly forward (to the left as shown in FIGURE 1) of the pivotal connection 49, and a plunger 53. This plunger 53 is telescopically en gageable with a sleeve 54 which is pivotally seated in a socket 56 in the end of the top handle 11. An overload release retention spring 57 urges the sleeve 54 and plunger 53 apart and thus roller 44 forward to the position shown in the drawing. This retains the transverse connector 43 in its downwardmost position and the overload release plates 39 in clockwise position. The fastening means 21 connecting the overload release plates 39 and punch holder 26 to the top handle side plates 14, 16 are thus retained against the clockwise end 48 of the slots 19, all of which is substantially as shown in FIGURE 1. When the connector pressure against the punch tips 37 exceed a pre determined amount and the punch holder 26 and overload release plates 39 cease clockwise rotation, further closing of the handles 11, 12 may still be accomplished. This is done by the force of the transverse connector 43 on the overload release plates 39 against the rollers 44, causing rearward telescopic movement of plunger 53 against the force of spring 57. This rotates bar 51 counterclockwise about pivot 52 to a less vertical position, permitting further closing of the handles to the position where the fastening means 21 abut the counter clockwise ends 47 t of the slots 19.

A feature of -the present invention is that the handles must fully close before the connector being crimped can be released from the punch tips 37 and withdrawn from opening 18. This insures that a predetermined minimum crimping effect has taken place to securely connect the connector and its conductor together. A ratchet mechanism is provided for this purpose. Rack 58 has an arcuate inner surface 59 with notches 61 thereon and is pivotally mounted on lower handle 12. A pawl assembly 62 is pivotally mounted on fastener 63 to the top handle side plates 14, 16. This assembly includes a triangular pawl 64 engageable with the notches 61 on rack 58 and a rearward extension 66 to which one end 67 of pawl assembly positioning spring 68 is attached. This spring 68 is of the compression type and, having its other end 69 fastened to the upper handle, continually urges rotation of the pawl assembly 62. When the rearward extension 66 is below pivot point 63, the spring 68 urges clockwise rotation of the assembly, freeing pawl 64 from engagement with the notches 61. This happens only when the handles 11 and 12 are completely closed and pawl 64 is urged upwardly by contact with flat face 71 on the closed end of rack 58. When this is done the handles may again be separated, causing counter rotation of the punch holder 26 and withdrawal of the punch tips 37 from engagement with the connector. When the handle are separated the hat surface 72 on the open end of rack 58 engages pawl 64 to cause counterclockwise rotation to lift the pawl extension 66 above pivot point 63. Spring 68 then urges further counterclockwise rotation to engage pawl 64 with the rack notches 61 for the next crimping operation.

Another feature of the present invention is the novel manner in which the crimping indentations are positioned along the axis of the connector. Positive stops are provided to limit inward movement of the connector into opening 18 for the various desired positions of the indentations along the axis. This is done with the connector depth selector mechanism 73 mounted on the other side of the opening 18 as shown in FIGURE 5 Here a knurled knob 74 is rotated until the proper color, designating the desired length, appears in the opening 76 in housing 77. A trigger 78, pivotally mounted on one of the top handle side plates 14, is actuated by a trigger thumb press 79 urged downwardly by the operator to permit an additional adjustment for a second crimp in axial spaced relation to the first crimp. This is more fully explained with reference to FIGURE 6.

The depth selector mechanism 73 shown in exploded four sides to provide indices for alignment of the recesses '82 with the connector opening 18. These flats are also color coded with proper nomenclature on the outside of the depth stop housing 77 to identify the type of connector to be used for the various positions of the plunger 81. The colored flats may be seen through a suitable opening 76 in the housing 77.

A depth selector plunger guide 87 retains the plunger 81 in its selected position. This guide is preferably of cylindrical configuration and is mounted on the tool in such manner that a central opening 88 in the guide is in axial alignment with the connector opening 18, shown in FIGURE 1. A transverse keyway' 89 extends across the outer portion of the guide to receive the depth selector plunger 81 in non-rotatable condition, the keyway walls 91 being spaced substantially the thickness of the plunger 81 between opposing flats 86. The guide 81 is counterbored on its inner surface 92 to receive a plunger pin trigger plate 93 for axially spacing at second crimp as will be more fully described. A suitable aperture 94 spaced from the central opening 88 in the se lector plunger guide 87 is for the purpose of receiving the depth selector plunger pin 84 for pivotal and axial movement. A selector knob 74 is engageable through offset opening 96 in the face of the stop housing 77 with sgosgsri the stem 97 on the outer surface of the lunger 81. A spring 98 over the stem 97 abuts the outer surface of the plunger 81 and the inner wall of the housing 77 to urge from engagement with the keywa 89. The knob 74 is then rotated (pin 84 in aperture 94 is in axial alignment with the knob 74') until the proper color appears in opening 76, whereupon the knob is'released and spring 98 again seats the plunger 81 in keyway 89 to prevent further rotation The trigger 78' and trigger plate 93" provide for axial spacing of a second crimp as in the" case of crimping coaxial cable wherein it is desired tocrir n'pthe connector to both the conductor andthe insulator portion. trigger plate 93 consists of a circular disc with a hole 101 in the center and a wedge-shaped cut 162 radiating out from the hole. A small aperture 103' is placed the same distance from the center as the pin receiving aperture 94 in the plunger guide 87. Trigger tip 1-04 fits within the wedge-shaped cut 102. A suitable recess 106 is provided in the plunger guide 87 to permit movement of the trigger tip 104 therein for aligning aperture 103- in the trigger plate 93 with the aperture 94 in the plunger guide 37 to permit the plunger pin 84 to be urged therein by spring 98. This moves the connector in an axial direction in an amount equal to the thickness of the trigger plate 93 so that a second crimp may be made. As previously pointed out with reference to FIGURE 2, the trigger 78 is pivotally mounted and actuated by pressing the trigger thumb press 79 downwardly to rotate the trigger plate 93 until its aperture 101 is in alignment with the aperture 94 of the lunger guide.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the term of the following claims:

1. A crimping tool for securing a connector to a conductor inserted therein comprising a pair of pivotally connected handles each having enlarged portions at their pivotal ends, means mounted on one of said handles adjacent the pivotal end thereof for determining the axial spacing of punch marks along the axis of said connector inserted, a rotatable punch holder connected to one of said handles and having punches mounted therein adapted for inward radial movement upon closing movement between said handles, overload release means for permitting continued closing movement between said handles without further movement of said punches when pressure exerted on said punches exceeds a predetermined limit, said overload release means comprising a release plate secured to said punch holder and rotatable therewith, resilient compression means engaging said release plate for rotation with one of said handles until force applied to said handle exceeds the force of said resilient compression means, and means connected to said handles for preventing outward radial movement of said punches until said handles have completed their closing movement.

2. A crimping tool for securing a connector to a conductor inserted therein comprising a pair of pivotally connected handles each having enlarged portions at their pivotal ends, the enlarged portions of one of said pair having a pair of outer plates With a connector receiving opening therein, means mounted on one of said plates adjacent the pivotal end thereof for determining the axial spacing of punch marks along the axis of said connector inserted in said opening, a rotatable punch holder having punches mounted therein for radial movement upon rotation of said holder, means connecting said punch holder to said outer plates for rotation therewith upon closing movement between said handles, overload release means for permitting continued closing movement between said handles without further rotation of said punch holder after a predetermined crimping pressure has been exceeded, said overload release means comprising a release plate secured to said punch holder and rotatable therewith, resilient compression means engaging said release plate for rotation with one of said handles until force applied to said handle exceeds the force of said resilient compression means, and means connected to said handles for preventing outward radial movement of said' punches until said handles have completed their closing movement.

3. A crimping tool for securing a connector to a conductor inserted therein comprising a pair of pivotally connected handles each having enlarged portions at their pivotal ends, the enlarged portions of one of said pair having a pair of outer plates with a connector receiving opening therein, means mounted on one of said plates over said opening for determining the axial spacing of punch marks along the axis of said connector inserted in said opening, the enlarged portion of the other of said pair of handles having a cooperating cam surfaced opening with a punch holder rotatably mounted therein, said punch holder having punches mounted therein for radial movement upon rotation of said holder within said cam surfaced opening, means connecting said punch holder to said outer plates for rotation therewith upon closing movement between said handles, overload release means for permitting continued closing movement between said handles Without further rotation of said punch holder after a predetermined crimping pressure has been exceeded, said overload release means comprising a release plate secured to said punch holder and rotatable therewith, resilient compression means engaging said release plate for rotation with one of said handles until force applied to said handle exceeds the force of said resilient compression means, and means connected to said handles for preventing outward radial movement of said punches until said handles have completed their closing movement.

4-. Means for exerting a uniform crimping pressure on connectors of various sizes comprising a crimping tool having movable punches for effecting crimping, handles for actuating said punches upon closure thereof, means for preventing outward movement of said handles until after a predetermined inward movement has been accomplished, and overload release means for permitting continued closure of said handles after a predetermined pressure has been exerted on said handles without further crimping action on said connector, said overload release means comprising a rotatable release plate rotatably attached to said one of said handles, and resilient compression means attached to said one of said handles and engaging said release plate for allowing rotation of said release plate with said one of said handles until the force applied to said handles in actuating said punches exceeds the force of said resilient compression means.

5. Means for exerting a uniform crimping pressure on connectors of various sizes comprising a crimping tool having movable punches for effecting crimping handles for actuating said punches upon closure thereof, ratchet means on said handles to prevent outward movement thereof until after a predetermined inward movement has been accomplished, and overload release means intercom necting said handles with crimping means for permitting continued closure of said handles after a predetermined pressure has been exerted on said crimping means without further crimping action on said connector, said overload release means comprising a rotatable release plate rotatably attached to said one of said handles, and resilient compression means attached to said one of said handles and engaging said release plate for allowing rotation of said release plate with said one of said handles until the force applied to said handles in actuating sa-id punches exceeds the force of said resilient compression means.

6. Means for exerting a uniform crimping pressure on connectors of various sizes comprising a crimping tool having radially movable punches for effecting crimping, handles for actuating said punches upon closure thereof, means on said handles for preventing outward movement of said handles until after a predetermined inward movement has been accomplished, overload release means interconnecting said punches and handles for permitting continued closure of said handles after a predetermined pressure has been exerted on said punches without further radial movement of said punches, said overload release means comprising a rotatable release plate rotatably attached to one of said handles, and resilient compression means attached to said one of said handles and engaging said release plate for allowing rotation of said release plate with said one of said handles until the force'applied to said handles in actuating said punches exceeds the force of said resilient compression means whereupon said release plate rotates relative to said one of said handles and against the force of said compression means.

7. Means for exerting a uniform crimping pressure on connectors of various sizes comprising a crimping tool having radially moveable punches for etfecting crimping, handles for actuating said punches upon closure thereof, ratchet means on said handles for preventing outward movement of said handles until after a predetermined inward movement has beenaccomplished, said ratchet means comprising a notched rack on one of said handles and a pawl assembly on the other of said handles, said pawl assembly including a pawl releasably engageable with said notches, means for urging said pawl into contact with said notches during handle closure, and overload release means for permitting continued closure of said handles after a predetermined pressure has been exerted on said handles without further crimping action on said connector, said overload release means comprising a release plate rotatably attached to one of said handles, and resilient compression means attached to said one of said handles and engaging said release plate for allowing rotation of said release plate with said one of said handles until the force applied to said handles in actuating said punches exceeds the force of said resilient compression means.

8. Means for exerting a uniform crimping pressure on connectors of various sizes comprising a crimping tool having a rotatable punch holder with radially moveable punches therein operable upon rotation thereof for effecting crimping, handles for actuating said punches upon closure thereof, ratchet means on said handles for preventing outward movement of said handles until after a predetermined inward movement has been accomplished, and overload release means for permitting continued closure of said handles after a predetermined pressure has been exerted on said punches without further crimping action on said connector, said overload release means comprising an overload release plate connected to said punch holder and rotatable therewith, resilient compression means releasably connecting said overload release plate for rotation with one of said handles until force applied to said handle exceeds the force of said resilient compression means.

References Cited in the file of this patent UNITED STATES PATENTS Re. 24,400 Garwood Dec. 10, 1957 733,998 Richards July 21, 1903 1,303,595 Rifilard May 13, 19 19 1,414,728 Enders May 2, 1922 2,079,498 Douglas May 4, 1937 2,086,400 Brenizer July 6, 1937 2,524,343 Diener Oct. 3, 1950- 2,552,602 Surline May 15, 1951 2,572,013 Cushman Oct. 23, 1951 2,577,199 Klopner Dec. 4, 1951 2,618,993 Carlson Nov. 25, 1952 2,753,742 Buchaman July 10, 1956 FOREIGN PATENTS 367,221 Great Britain Feb. 18, 1932 

